CHAPTER XXX. 



THE CHOLERA SPIRILLUM (SPIRILLUM CHOLERA ASIATICS) 

 AND ALLIED VARIETIES. 



Ix INV') Koch separated a characteristically curved organism from 

 the dejecta and intestines of cholera patients the so-called "comma 

 bacillus." This he declared to be absent from the stools and intes- 

 tinal contents of healthy persons, and of persons suffering from other 

 affections. The organism was said to possess certain morpholog'cal 

 and biological features which readily distinguished it from all previously 

 described organisms. It was absent from the blood and viscera, and 

 was found only in the intestines; and the greater the number, it was said, 

 the more acute the attack. Koch also demonstrated an invasion of 

 the mucosa and its glands by this "comma bacilli." The organisms were 

 found in the stools on staining the mucous flakes or the fluid with 

 methylene blue or fuchsin, and sometimes alone; by means of cultiva- 



Fir,. 120 FIG. 121 



Contact smear of colony of cholera spirilla Cholera spirilla preparation from gelatin-plate 



from a gar. X 700 diameters. (Dunham.) culture of cholera. X 800 diameters. 



tion on gelatin they were readily separated from the stools. During 

 his stay n India, in Ku'vpt, and' at Toulon, Koch had examined over 

 one hundred cases, and other investigators confirmed his statements. 

 Numerous control observations made upon other diarrhoeic dejecta 

 and upon normal stools were negative; the comma bacillus was found 

 in choleraic material only, or in material contaminated by cholera. 

 Soon, however, other observers described comma-shaped organisms 

 of non-choleraic origin. Kinkier and Prior, for instance, found them 

 in the diarrhu*al >t<>nlsnf cholera nostras, Deneke in cheese, Lewis and 

 Miller in saliva. All of these organisms, however, differed in many 

 respects from Koch's comma bacillus, and it has since been proved 



